badge

1a small piece of metal or plastic, with a design or words on it, that a person wears to show that they belong to an organization, support something, have achieved something, have a particular rank, etc.a Girl Scout badgeAll employees have to wear name badges.comparebutton

2a small piece of metal that you carry or wear to prove who you are, used, for example, by police officersHe pulled out a badge and said he was a cop.

3badge of honor/courage(formal)something that you are proud of or that shows how brave you areHe wore his working-class background like a badge of honor.